Concerns about the quality and safety of our environment have evoked a growing awareness of the hazards associated with diverse organic and metal pollutants in groundwater from Superfund sites and (more recently) drinking water and foods destined for human consumption. Many of these prioritized environmental contaminants (ECs) can have severe and long lasting effects on health. The scope of the problem is broader still, since ECs routinely occur as complex mixtures, the toxicities and interactions of which are ill-defined. Clearly, appropriate and practical intervention strategies for the remediation of contaminated food and water and the prevention of EC-induced disease in humans are high priorities. In this project, our specific aims are fourfold, and based on the central hypothesis that effective sorbent-based interventions can be developed to significantly diminish exposure (and risk) from EC-contaminated water and food. It is further postulated that EC-selective composite media and optimal binding agents can be developed to purify groundwater, as well as diminish the bioavailability of ECs from the gastrointestinal tract of humans and animals when included in the diet, Our experiments will focus on identifying and investigating high affinity sorbents and multifunctional binding agents for the remediation of ECs (i.e. PAHs, chlorinated organics, and toxic metals) via water purification or by enterosorbent therapy through the diet. Binding agents will encompass a variety of clay and zeolitic minerals, biopolymers, and antibody-based materials, as well as chemically modified analogs and optimal composite mixtures. Also, "iron-impregnated" and "amended clay-encapsulated" chitosan gel beads and analogs will be developed and tested for their ability to sequester arsenic and TCDD from aqueous solutions and for their efficacy in preventing the toxicity of arsenic and TCDD in utero. In inter-project collaboration, folate transport deficient mice and Ah/R knockout mice will be used as genetically sensitive models for arsenic and TCDD, respectively. !n these studies, we will determine if prioritized enterosorbents, provided as dietary supplements, can rescue mice from teratogenesis and developmental toxicity when challenged by sodium arsenate and TCDD. The long-term goal of this project is to provide innovative chemical and biological interventions that will enhance environmental risk management by reducing exposure of humans and animals to high priority ECs from water and food.